The convoy did not include the combatant ships of Admiral Halsey’s Third Fleet. The main striking force of the Third Fleet was Task Force 38, composed of four powerful carrier task groups, under Admiral Mitscher. Each group contained fast carriers, cruisers, destroyers, and the newest American battleships.[13]
After forming, the convoy proceeded toward the target. At this time a disquieting report was received from the meteorologists on board the ships: a typhoon was headed toward the Leyte Gulf area. Such a disturbance could be fatal to the expedition. A severe storm did in fact lash the gulf area from 14 through 17 October, but it gradually abated and the morning of A Day, 20 October, was clear. This favorable weather augured well for a successful landing.
Softening the Target
Early Strikes
Allied aircraft had already visited the Philippine Archipelago. The first aerial strikes since 1942 were made in the early fall of 1944. On 1 September B-24’s from New Guinea bases initiated their first large-scale air attack against airdromes in the Davao area, though bad weather prevented the protective fighter escort from attacking the target. The airborne defense encountered was surprisingly light—only three intercepting fighters opposed the strike. The bombers dropped 100 tons of bombs, destroying 34 planes on the ground and killing about 100 men.[14] Two American bombers were shot down and six received minor damages.[15] General MacArthur believed that the Japanese were conserving their air strength in order to concentrate it against anticipated Allied landings.[16]
On 4 September the first aerial reconnaissance flights were made over Leyte. During the period 9–14 September, Admiral Mitscher launched a large-scale, carrier-based air assault against the Japanese air defenses in the Philippine Islands in order to protect the Palau and Morotai landings. On 9 September aircraft from the carriers attacked airdromes and installations in the Mindanao area, destroying 60 aircraft on the ground and 8 in the air. On 12 September the attack was directed against the Visayan Islands. Of an estimated air strength of 225 aircraft in the sector, 125 were destroyed on the ground and 75 in the air. During the night of 12 September the Japanese flew in reinforcements from Luzon. A Third Fleet strike on 13 September against the reinforced air strength destroyed an estimated 135 aircraft on the ground and 81 in the air. On the 14th, the Third Fleet planes encountered no enemy air opposition but destroyed from 10 to 15 aircraft on the ground. The air strength which the enemy had conserved for an anticipated American invasion was thus decimated. About 500, or approximately 57 percent of the 884 aircraft believed to be in the Philippines, were rendered nonoperational or destroyed. This successful knocking out of the Japanese air strength in the Philippine Islands was an important factor in the decision to speed up the landing at Leyte by two months.
On 21 September Central Pacific carrier-based aircraft directed their attention to the Luzon area. In spite of their vigorous defense of the Luzon airfields, the Japanese lost an estimated 110 aircraft in the air and 95 on the ground. These included not only combat aircraft but also reconnaissance, transport, and training planes. The remaining air strength in the area was estimated to be 350 aircraft, of which 10 percent were in Mindanao, 20 percent in the Visayan Islands, and 70 percent in Luzon.
At the same time, the carrier-based aircraft made strong strikes against enemy shipping in the central and southern Philippines. It was estimated that from 1 September to 15 September 105 merchant vessels were sunk in those waters by carrier planes, destroyers, cruisers, and submarines. Although exact information was lacking on the number of enemy vessels present in the Visayan and Mindanao areas, it was thought that 50 percent of the Japanese merchant marine in those areas was eliminated. A successful attrition of the Japanese air and naval strength in the Philippines had been accomplished.[17]
The Third Fleet’s carriers then started to neutralize the approaches to the Philippine Islands. The carrier-based aircraft launched strikes against enemy aircraft staging areas in the Ryukyus, of which Okinawa is the largest and most important. As a result of attacks on 10 October, they destroyed an estimated 23 enemy planes in the air and 88 on the ground or in the water. Admiral Halsey reported that his flyers sank 1 subtender, 1 mine sweeper, 1 destroyer escort, 2 mine-craft, 4 midget submarines, 20 cargo ships, and 45 other craft. In addition, nearly as many ships, mostly of small size, were damaged.[18] On 11 October the flyers struck at Luzon.